The present invention is directed to a chair and a method of its construction. The primary purpose of the chair of the present invention is to provide a chair construction where the suspended supporting surface is constructed of rigid blocks strung by a rope between the side panels of the chair in such an arrangement to flex and conform to the posture of a sitting person.
In constructing chairs designed for casual or outdoor use that may be subject to hard use or the outdoor elements, it is not feasible to use padding or stuffing materials to provide comfort for the person sitting in the chair; rather, such chairs may be made of hard, rigid materials or may be made of a flexible fabric stretched between rigid side panels. The problem with each of these chair constructions is that the supporting surfaces do not provide a comfortable seating surface. Prolonged sitting on a hard rigid surface is not normally comfortable and can lead to backaches and, on occasion, more serious back problems. While prolonged sitting on a flexible fabric surface may be more comfortable than sitting on a hard surface back problems can also develop since the back is not properly supported. In addition, quite often chairs with flexible fabric supporting surfaces are difficult to arise from and in particular, where the weight of the person actually stretches the fabric forming a basket-like shape which hangs below the supporting frame; further, chairs with fabric supporting surface do not generally provide the strength that chairs formed entirely of rigid materials do. U.S. Pat. No. 3,909,064 issued to Payne et al. is directed to a chair construction where a plurality of rigid slats padded with a foamed plastic and covered with a canvas material extend between opposite side panels forming the seat and backrest supporting surface. Even though the slats are padded to provide a comfortable supporting surface the fact remains that the slats are hard and rigid and do not conform to the posture of a person.
British Pat. No. 14,512 issued July 28, 1894, is directed to a flexible chair supporting surface including a plurality of hard rigid slats strung in a vertical direction between the head rest and the front cross member of the chair seat. While the slats are strung on a rope and do flex, they can only flex in one direction in relation to a person's sitting posture, therefore providing only partial comfort.
U.S. Pat. No. 390,393 issued to Norris is directed to a hammock which includes a plurality of interfitting slats strung on a rope and designed to flex by pivoting on a supporting rope.
Other prior U.S. patents which disclose rigid slats strung on a rope to provide a supporting surface include U.S. Pat. Nos. 374,472 issued to Hartman, 2,551,976 issued to Smith and 2,745,473 issued to Boland.
In reviewing the above-mentioned patents, it is particularly noted that many of the above described constructions take the form of a plurality of slats suspended to extend generally perpendicular to the backbone or to the length of a person sitting in the chair. Significantly, such slats provide a rigid support in a direction across the person's body, thus not conforming to the body of a person sitting in the chair.
U.S. Pat. No. Des. 172,858 does show a plurality of blocks suspended in rows to form a seating surface for a chair construction. However, said blocks are suspended by horizontal and vertical straps whereby the blocks appear to be held in a relatively rigid fashion to permit but a limited amount of flexing to contour to the body of the person sitting within the chair. Further, it appears that the straps that are disposed in rows and columns are affixed at each end to rigid support members and if in the course of continued use these straps do stretch, there is no provision for retensioning them. Further, two support members extend in a direction perpendicular to the body of the person sitting within the chair, thus preventing those blocks suspended close thereto, from fully flexing with respect to the person's body.
The prior art also includes a chair construction including a pair of side panels and a backrest and seating portion formed of a plurality of blocks suspended between the side panels by a rope. In such construction, the rope extends between the side panels and suspends the blocks in rows thereof. In particular, the rope extends through openings within the blocks and knots are formed within the rope between each of the blocks in a row. Thus, the blocks are not free to move longitudinally along the length of the rope and are limited as to their flexibility in conforming to the body of the person sitting in the chair. It is also desirable to permit the person sitting in the chair to reform or reshape various portions of the chair to fit his own individual body, which is prevented in that each block and row of blocks is permitted a limited amount of flexing and movement with respect to the body of the person sitting in the chair. Further, after prolonged use of the chair, the rope suspending the blocks may be stretched so that portions of the chair may unduly sag. In a chair where knots are inserted between each block, it is impossible to reapply tension to the rope to recondition the chair structure and to eliminate sagging that may occur.